We are gathering requirements for a validation tool for Twitter Cards, please chime in this thread to help us help you.
Would love something like the Facebook linter:
or Google’s rich snippets tester:
doesn’t even have to be with a preview in the first instance, although that might not be the hardest part to build.
Next to showing the parsed data, the tool should also force a re-fetch… It’s now impossible (AFAIK) to force a respider / refetch of a page, so you can’t see whether your changes worked…
I concur with @yoast
Facebook’s Debugger or Google’s Rich Snippets Testing Tool are both good ones to emulate. The real key is to keep the validation tool stable (which Google has not) and informative.
Highly descriptive error messages or warnings would be an excellent way to launch a Twitter Card validator. In short, if someone gets it wrong, do everything you can to tell them why it’s failing and how to correct it.
Just make sure it works - I am currently getting the following validation message:
Validation failed for image with width = 300px, height = 300px. Square images must have dimensions of at least 262x262. 16:9 images must have dimensions of at least 350x196. Url: (…)
Edit: This was working yesterday and I was about to submit for a whitelisting
I know I may have placed this in the wrong spot - apologies - please feel free to move it if you wish - fixed this by sending it a pic 350 x 265. Still don’t know why the square would not work, but hey, I real validation tool that explained why the error was occuring would be helpful.
So I guess to topic, +1 to @ajkohn on error messaging
The image validation error is a bug on our side, should be fixed now.